1. Field of the Invention
The present invention relates to a digital mixing system that has a plurality of input signal systems and a plurality of output signal systems to subject input signals from the plurality of input signal systems to a mixing process and output the mixed input signals to the plurality of output signal systems, as well as an engine apparatus, a console apparatus, a digital mixing method, an engine apparatus control method, a console apparatus control method, and programs executing these control methods.
2. Description of the Related Art
Conventionally, mixing consoles are well known, which adjust the levels and frequency characteristics of audio signals output from a large number of microphones or electric or electronic instruments, mix these signals into several mixing groups, and collectively transmit these mixing groups to a power amplifier. An operator operating the mixing console operates various panel buttons (panel operating elements) provided on the mixing console to adjust the volume and tone of each audio signal for an instrumental sound or a singing voice so that the signal most properly expresses the actual performance. The mixing console is provided with a plurality of microphone/line input channels as input signal systems. The input signal systems are programmed and signals from the input signal systems are subjected to a mixing process, and the mixed input signals are output to a plurality of output channels as output signal systems. In general, signals on the input channels of the input signal systems are amplified by a head amplifier and then output to a mixing processing section. Then, the mixing processing section adjusts the frequency characteristics and levels of the amplified signals on the respective input channels and mixes these signals in a programmed combination. Then, the resulting mixed signals are each set by an output fader to a desired output level and then output to one of the output channels.
Such a mixing console is used in theaters or concert halls or in recording studios to create music sources to be recorded on compact disks (CDs). For example, when the mixing console is used in a concert hall, a large number of microphones are installed on a stage, and instrumental sounds or singing voices are input to the mixing console through the microphones. The mixing console adjusts the levels or frequency characteristics of a large number of input microphone/line signals, mixes these signals in a desired combination, and then outputs the mixed signals to a power amplifier that drives speakers.
Since a large number of microphone/line signals are input to such a mixing console via respective cables, a large number of cables are connected to the mixing console. In a concert hall, the mixing console may be installed in the vicinity of the stage, but, in general, it is installed in an area of seats for the audience, which is remote from the stage, or in a mixer room provided behind the area of seats for the audience, in order to allow the operator to perform a mixing operation while checking sound being listened to by the audience. Thus, long cables are required to input microphone/line signals to the mixing console, and the operation of laying such cables is cumbersome and time-consuming. Furthermore, the longer the cables are extended, the more likely the mixing console is to be affected by noise.
To solve this problem, a mixing system has been proposed, in which an engine section that mixes input microphone/line signals is separated from a console section that controls a mixing process, the engine section and the console section being connected together via communication lines. With this mixing system, the engine section that executes a mixing process can be installed in the vicinity of the stage, while the console section can be installed in the area of audience seats, thereby allowing the operator to control the mixing process while checking sound being listened to by the audience. Moreover, microphone/line signals are input to the engine section that executes the mixing process, thereby making it easier to perform the operation of laying the cables. Further, this system does not require the use of long cables and can thus prevent noise.
However, if the engine and console sections are separated from each other and connected together via the communication lines, then for convenience' sake, each of these sections is provided with input terminals for control signals from external devices. Then, the mixing process is controlled in accordance with control signals input to the engine and console sections. In this case, the system must operate consistently irrespective of whether a control signal is input to the engine section or the console section. Disadvantageously, no method has been established to achieve such a consistent operation.
Further, when the engine and console sections are separated from each other and connected together via the communication lines, if a disconnection occurs in the communication lines for any reason, the entire mixing system may disadvantageously become inoperative even if the engine section is not defective. Furthermore, if a fault occurs in the console section, the entire system may disadvantageously become inoperative even if the communication lines and the engine section are not defective.
Further, the engine and console sections of the mixing system each have arithmetic means for controlling the operation thereof. However, the engine and console sections can be separated from each other and the connection therebetween can be flexibly changed, thereby hindering the collective upgrading of operation software used by the respective arithmetic means.
Moreover, if the engine section that executes a mixing process is installed in the vicinity of the stage, and the console section is installed in the area of audience seats, then the operator controls the mixing process while checking sound being listened to by the audience. In this case, a time delay occurs before sound emitted from stage speakers reaches the operator in the area of audience seats, because of the long distance between the speakers and the operator. On the other hand, the operator carries out a mixing operation by operating panel buttons provided on the console section, and monitors signals resulting from mixing performed in accordance with the mixing operation by the engine section, through monitor speakers or a monitor headphone. However, since sound emitted from the stage speakers reaches the operator with a time delay, a time difference occurs between the sound emitted from the stage speakers and the sound being listened to by the operator through the monitor speakers or monitor headphone. Consequently, it is very difficult for the operator to properly evaluate the mixed signals.
Further, the mixing system is provided with a talk back function for enabling the operator operating the console section to communicate with staff on the stage. For example, when a talk back switch provided on the console section is depressed, a microphone input to the console section is turned on so that the operator's voice sound is emitted from a monitor speaker on the stage. If the stage staff communicates with the operator at the console, he uses any one of analog input channels to the engine section to input his voice so that his voice sound is emitted from the monitor speakers of the console section. However, such communication is impossible unless the operator at the console section has enabled the channel assigned for the communication. Further, monitor sound for use in monitoring sound from the stage speakers is also emitted from the monitor speakers, and the voice sound for communication between the stage staff and the operator may be drowned by the monitor sound. Moreover, one of the input channels must be used for the communication, thereby limiting available resources.